This invention relates to metal wood golf clubs, and, more particularly, to a metal wood golf club which includes a permanently attached internal gate.
Metal wood golf clubheads are conventionally formed by investment casting using the lost wax process. A wax impression of the hollow clubhead is made, and a mold is formed around the was impression. The wax is melted and removed to form a mold cavity in the mold. The wax impression includes a gate portion which forms a gate or passage in the mold which connects the mold cavity to the exterior of the mold. The gate is usually located at the toe or heel portion of the clubhead.
Molten metal is poured into the gate of the mold and flows into the mold cavity. After the metal cools to form the clubhead, the mold is broken up and cleaned away from the clubhead. The solid metal which occupied the gate portion is removed from the clubhead, and the gate area is ground and buffed to provide a smooth exterior surface.
The size of metal wood clubheads has increased in recent years, and larger clubheads often require additional external gates on the crown or top of the clubhead and/or the skirt or sides of the clubhead in addition to the main external gate to facilitate flow of molten metal throughout the mold cavity, to improve casting, and to reduce surface porosity on the molded clubhead. The external gates require additional processing steps and additional material and form molded metal material which must be removed from the cast clubhead.